Endothelium-dependent vasodilator effect of extract prepared from the seeds of Areca catechu on isolated rat aorta

Arecae semen extract relaxed aortic ring preparations of isolated rat aorta that contained endothelium from 3×10⁻⁷ g/mL, reaching a maximum of 86% at 10⁻⁵ g/mL. Its relaxation did not occur in specimens without endothelium, and was inhibited by pretreatment with 10⁻⁴ M N^G-nitro-1-arginine methylester. One of the active components was arecoline which is a muscarinic receptor agonist. Another active component was condensed tannin contained in Arecae semen. © 1997 John Wiley & Sons, Ltd.